Sewage/wastewater treatment system using granular activated sludge and membrane bio-reactor and sewage/wastewater treatment method using the same

Abstract

The present disclosure relates to a sewage/wastewater treatment system using granular activated sludge and a membrane bio-reactor and a sewage/wastewater treatment method using the same that are configured to effectively remove pollutants contained in raw water through a granulation tank in which the granular activated sludge is contained and to allow the raw water to be filtered through movable membranes located on the upper portion of the granulation tank. The system includes: an indirect aeration tank adapted to supply air thereto to allow dissolved oxygen contained in raw water to reach a saturation concentration; a granulation tank adapted to allow floating microorganisms contained in the treated water passing through the indirect aeration tank to be granulated and having a sludge blanket formed thereon; and movable membranes located on the upper portion of the granulation tank in such a manner as to be movable in the granulation tank.

What is claimed is: 
     
       1. A raw water treatment system using a granular activated sludge blanket and submerged movable membranes, the system comprising:
 an indirect aeration tank adapted to supply air to the indirect aeration tank and to treat raw water by allowing dissolved oxygen contained in the raw water to reach a saturation concentration; 
 a granulation tank adapted to allow floating microorganisms contained in treated water passing through the indirect aeration tank to be granulated and form the granular activated sludge blanket in a lower portion of the granulation tank; and 
 the submerged movable membranes located in an upper portion of the granulation tank and adapted to be movable in the upper portion of the granulation tank, 
 wherein the granulation tank includes an agitator adapted to agitate the granular activated sludge blanket using a single motor for driving the submerged movable membranes in the granulation tank. 
 
     
     
       2. The system according to  claim 1 , wherein the granulation tank is adapted to produce gelatin as by-product of contact of the floating microorganisms, to apply a first hydrodynamic force caused by the treated water conveyed from the indirect aeration tank, and to apply a second hydrodynamic force caused by the agitator of the granulation tank. 
     
     
       3. The system according to  claim 1 , wherein the agitator is disposed inside the lower portion of the granulation tank. 
     
     
       4. The system according to  claim 1 , wherein the submerged movable membranes include microfiltration MF membranes or ultrafiltration UF membranes. 
     
     
       5. The system according to  claim 1 , further comprising a partitioning wall that divides an interior of the granulation tank into the upper and lower portions. 
     
     
       6. The system according to  claim 5 , wherein the partitioning wall includes a porous member or inclined plates arranged at intervals. 
     
     
       7. The system according to  claim 1 , further comprising a reciprocating device adapted to reciprocate the submerged movable membranes in the granulation tank. 
     
     
       8. The system according to  claim 7 , wherein the reciprocating device comprises:
 the single motor; 
 sliding frames reciprocatingly connected to the submerged movable membranes; and 
 rotors connected to the sliding frames by rotational shafts, 
 wherein the single motor is adapted to rotate the rotors and to convert rotational motion of the rotors into reciprocating motions of the sliding frames through the shafts connected to the sliding frames. 
 
     
     
       9. The system according to  claim 8 , wherein the reciprocating device further comprises buffers disposed between the sliding frames and the shafts. 
     
     
       10. The system according to  claim 8 , wherein the sliding frames are varied along sliding rails on which linear bearings and shaft-supports are disposed. 
     
     
       11. The system according to  claim 1 , wherein the submerged movable membranes are adapted to selectively or continuously move while supernatant liquid in the granulation tank is filtered. 
     
     
       12. A raw water treatment system using a granular activated sludge blanket and submerged movable membranes, the system comprising:
 an indirect aeration tank adapted to supply air to the indirect aeration tank and to treat raw water by allowing dissolved oxygen contained in the raw water to reach a saturation concentration; 
 a granulation tank adapted to allow floating microorganisms contained in treated water passing through the indirect aeration tank to be granulated and form the granular activated sludge blanket in a lower portion of the granulation tank; 
 the submerged movable membranes located in an upper portion of the granulation tank and adapted to be movable in the upper portion of the granulation tank; and 
 an auxiliary water circulation line adapted to allow the treated water passing through the granular activated sludge blanket to be circulated again from the upper portion of the granulation tank directly to the lower portion of the granulation tank. 
 
     
     
       13. The system according to  claim 12 , wherein the auxiliary water circulation line is adapted to circulate the treated water by a force generated from movements of the submerged movable membranes in the granulation tank. 
     
     
       14. The system according to  claim 12 , wherein the auxiliary water circulation line is formed on an outside of the granulation tank and includes a motor or deceleration member installed in the auxiliary water circulation line to selectively control a flowing speed of the treated water from the upper portion of the granulation tank to the lower portion of the granulation tank. 
     
     
       15. The system according to  claim 12 , further comprising a reciprocating device adapted to reciprocate the submerged movable membranes in the granulation tank, the reciprocating device comprising:
 sliding frames reciprocatingly connected to the submerged movable membranes; 
 rotors connected to the sliding frames by rotational shafts; and 
 a motor that rotates the rotors and converts rotational motion of the rotors into reciprocating motions of the sliding frames through the shafts connected to the sliding frames, 
 wherein the granulation tank is adapted to apply agitating effects to the granular activated sludge blanket without disposing an agitator in the granulation tank.